Explosive video reveals that George Zimmerman appeared uninjured when he arrived at a Florida police station the night he shot Trayvon Martin — his nose is not broken or bleeding and the back of his head is unmarked by grass or bruising. The Sanford, Fla., Police Department says it did not arrest the Hispanic neighborhood watchman who killed the unarmed black teenager because Trayvon was pounding his head into the ground and Zimmerman shot...